Two new upland rice varieties, YARA and PAYA, were developed for smallholder farmers in Bolivia through collaboration between MAN-B, CIAT Santa Cruz, and CIRAD/CIAT. YARA and PAYA were selected for their adaptation to small farm conditions, good agronomic characteristics, drought tolerance, and resistance to lodging and shattering. In field trials, YARA yielded an average of 3,900 kg/ha and PAYA yielded 4,200 kg/ha. Both varieties are recommended for upland hillside ecosystems in Bolivia.

1. “YARA & PAYA”
Two new Upland Rice Cultivars for the small-holders of Bolivia
Cruz J. 1, Guitièrrez R.1, Carizales G.2, Taboada R.2, Viruez J.2, Châtel M.3, Ospina Y.3, Grenier C.3, Rodriguez F.3
1MAN-B Bolivia, 2CIAT Santa-Cruz Bolivia, 3CIRAD/CIAT Colombia
Introduction
In Bolivia, rice is a very important staple food. Consumption
is steadily increasing reaching in the recent years 35 kg. per capita.
Two main rice production ecosystems are present:
(1) the upland mechanized ecosystem where the Province of Santa Cruz
represents 75% of the total Bolivian rice area and produces 80% of the total
national rice production and (2) the manual ecosystem, present in all the
Bolivian Provinces, where rice is produced by small farmers.
Following request from rice producers of North La Paz to improve
production conditions, MAN-B and CIAT Bolivia achieved a technical
cooperation agreement for the development of rice varieties meeting the
characteristics required by rice producers, such as medium size grain, good
yield, drought tolerance, earliness, resistance to lodging and shattering, and
tolerance or resistance to disease such as blast. Bolivian hillsides at Caranavi
The success in developing and releasing new varieties was possible through
the collaborative work that MAN-B, CIAT Santa-Cruz and the Cirad/CIAT
project (Colombia) have done since 2002. Cirad/CIAT shared germplasm and
technology with CIAT-SC, and MAN-B requested germplasm from CIAT-
SC with the goal of obtaining high yielding rice varieties for the medium and
long term, and focusing on participatory plant breeding approach. This
objective was achieved through the release of these new varieties.
New variety for the small farmers
The new upland rice varieties YARA and PAYA are lines that originate from
the Cirad/CIAT composite population PCT-11, were selected by CIAT-SC,
and introduced in the Department of La Paz by MAN-B. The lines passed YARA. Small-holder’s field
through the different agronomic selection and evaluation trials and were
identified as promising because of their adaptation to the small-farmers
conditions and good agronomic characteristics.
PAYA. Seed production field
Variety Characteristics
YARA PAYA
Average yield from field trial …..… (kg/ha). 3900 Average yield from field trial …..… (kg/ha). 4200
Initial plant vigor .................................... Vigorous Initial plant vigor .................................Strong vigor
Days to maturation........................................... 130 Days to maturation........................................... 125
Plant height (cm)............................................. 120 Plant height (cm)............................................. 132
Lodging.................................................... Resistant Lodging.....................................Moderate resistance
Panicle exertion ………… ...................... Emerged Panicle exertion ………… ...................... Emerged
Panicle length (cm).......................................... 23.6 Panicle length (cm).......................................... 28.4
Grain number per panicle ................................ 123 Grain number per panicle ................................ 159
Maturity percentage ........................................ 73.6 Maturity percentage ........................................ 77.8
Panicle number per m2 .................................... 212 Panicle number per m2 .................................... 231
Shattering ................................ Moderate resistance Shattering ................................ Moderate resistance
PAYA. Filled panicles
Recommendations
PAYA and YARA varieties are recommended to small-farmers for
the upland hillside ecosystem with intermediate altitude. The same
varieties can also be produced in the production areas of the
department of La Paz as in Caranavi, Teoponte, Guanay, Palos
Blancos, San Buenaventura, Ixiamas, etc.
Field day by MAN-B